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Entry  Fri Sep 16 17:16:15 2011, Jenne, Update, SUS, Input matrix diagonalization: Fail! 
    Reply  Fri Sep 16 23:22:36 2011, kiwamu, Update, SUS, ETMX input matrix : bad YAW-SIDE coupling 
       Reply  Sat Sep 17 02:07:10 2011, kiwamu, Update, SUS, ETMX input matrix : bad YAW-SIDE coupling 
Message ID: 5444     Entry time: Fri Sep 16 23:22:36 2011     In reply to: 5438     Reply to this: 5446
Author: kiwamu 
Type: Update 
Category: SUS 
Subject: ETMX input matrix : bad YAW-SIDE coupling 

With the new input matrix, it looks like YAW and SIDE are not quite decoupled on ETMX.

It needs one more kick and free swinging test.

 

- - - details

 To see what exactly is going on, I changed the input matrix from the default to the new one, which Jenne computed (#5421) on ETMX.

I started putting the elements of the input matrix from POS through SIDE, one by one.

It seemed that POS and PIT worked fine. However the YAW signal looks containing a lot of the SIDE signal.

Similar to YAW, SIDE also interact with the YAW motion and somehow rings up both YAW and SIDE signals as Jenne reported ( #5438).

So right now the YAW and SIDE rows are partially reburted to the default elements in order to avoid ringing up.

Quote from #5438

but ETMX and BS were not good at all.  ETMX was ringing up when I turned on the damping. 

 

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